The Reagan administration was accused yesterday of circumventing Congress by dusting off old laws and writing new regulations to achieve a new era of secrecy in this country.

The charges were made at a joint hearing of two House subcommittees on President Reagan's latest directive, issued March 11, requiring federal employes with security clearances to sign non-disclosure agreements and to submit to lie detector tests if asked.

New York lawyer Floyd Abrams, a leading expert in First Amendment cases, said that the order dovetails with the administration's information policies, which he called "unique in recent history."

Those policies, Abrams said, "are coherent, consistent and, unlike those of some recent administrations, not a bit schizophrenic." He protested that they also are consistently at odds with the notion that a free flow of information is in the public interest.

Examples cited by Abrams and other witnesses at the House hearing and later in the day at a Senate hearing on proposed revisions in the Freedom of Information Act included:

The Department of Commerce has relied on the Export Administration Act to sanction government intervention into unclassified university research. For instance, Abrams said, the law was invoked to prohibit an American professor from reading an academic research paper containing unclassified information at a scholarly conference attended by U.S. nationals.

The Foreign Agents Registration Act was interpreted to require that the Academy Award-winning documentary from Canada, "If You Love This Planet," be treated as political propaganda even though the law specifically "excepts from its coverage films 'not serving predominantly a foreign interest.' "

The McCarran-Walter Act has been used lately to bar a wide range of individuals from this country by denying them visas, including the widow of the late Chilean president Salvador Allende and spokesmen for opposing radical groups in Northern Ireland.

U. S. Customs laws have been invoked in an effort to prevent American writer William Worthy from bringing in books "sold freely on the streets of Tehran," because they allegedly contained documents seized from the former U.S. Embassy there.

The Freedom of Information Act repeatedly has been interpreted in restrictive fashion. The Justice Department has issued guidelines discouraging fee waivers and calling on govermment agencies to scrutinize the "qualifications" of those who request documents, as well as what they mean to do with the documents.

In another recent instance, cited by the Society of Professional Journalists, the CIA demanded a $1,520 search fee, half of it payable in advance, from a Fordham University professor who was seeking the full text of a two-page memo about counterespionage efforts in Ireland during World War II.

In the Reagan administration, Abrams said, "It is almost as if information were in the nature of a potentially disabling, contagious disease, which must be feared, controlled and ultimately quarantined."

Abrams said he did not mean to suggest that previous adminstrations have not done some of the same things, but he argued that what is new is the "across-the-board rejection" of the values of an informed public.

Other witnesses joined in criticizing the president's March 11 directive, which also would require federal government officials with access to especially sensitive information to submit any writing based on their government service to government censorship.

Rep. Patricia Schroeder (D-Colo.), who presided at the House hearing with Rep. Don Edwards (D-Calif.), said that the directive was issued without any showing of need, and added that she suspected it would be used selectively against critics and whistle blowers.

At the Senate hearing, the leadoff witness was FBI Director William H. Webster, who urged passage of a Judiciary Committee bill that would exempt organized crime records and many other FBI documents that now come under the Freedom of Information Act.

Webster said that criminals were making increasingly sophisticated use of the law in an effort to identify government informers and frustrate investigations.